The continuing escalation in the incidence and prevalence of HIV disease and in associated resource and training needs is beginning to have severe impacts on many state Medicaid programs, which provide medical care for up to 60% of people with AIDS (PWAs). Clinical research has established the efficacy of pharmaceutical agents such as zidovudine and pentamidine for increasing survival and reducing the risks of opportunistic infections. Yet little is known about the quality, costs, and overall patterns of medical care provided to vulnerable Medicaid populations such as low-income women and children with HIV disease, particularly those outside the mainstream medical care system who may not be adequately represented in previous research studies. Such information can be useful in targeting and implementing quality improvement programs to correct gaps in quality of care in specific patient and physician populations. We will link New Jersey Medicaid eligibility and claims data with surveillance data from the New Jersey Department of Health's AIDS Registry from 1987 to 1991. We validate Medicaid AIDS data with information from the Registry and determine the sensitivity and specificity of our Medicaid-based identification process. To our knowledge, this will be the largest linked Medicaid-AIDS Registry' database on HIV-infected women and children in the U.S. We will define quality of care indicators that can be used to (1) monitor progress in adherence to treatment guidelines over time, and (2) detect variations in patterns of care between and within three cohorts of patients (women, children and male intravenous drug users) and prescribing physicians. We will examine variation among primary physician caregivers in specialty and training and in predominant settings (in private practice, drug abuse clinics, outpatient hospital clinics, etc.) for' services provided to low-income, HIV-infected women and their children and adult, male intravenous drug users. Using survival analysis methodologies, the investigation will encompass three phases: (1) description of patterns of care among the patient subgroups; (2) trends and variation in adherence to scientifically-based clinical guidelines, with a primary focus on HIV-infected women; (3) predictors of variation in treatment of HIV-infected women by patient, physician and setting characteristics.